1. Field of the Invention
This invention relates to methods of producing compositions and is particularly directed to a method of producing NF.sub.4 PF.sub.6 by a displacement reaction between NF.sub.4 BF.sub.4 and PF.sub.5.
2. Description of the Prior Art
NF.sub.4.sup.+ salts are the key ingredients for solid propellant NF.sub.3 --F.sub.2 gas generators, such as that disclosed by D. Pilipovich in U.S. Pat. No. 3,963,542, for chemical HF-DF lasers. Whereas NF.sub.4 SbF.sub.6 and NF.sub.4 AsF.sub.6 can be prepared with relative ease, according to the methods taught by W. E. Tolberg et al, in U.S. Pat. No. 3,708,570, and K. O. Christe et al, in U.S. Pat. No. 3,503,719, these compounds suffer from the disadvantage of containing a relatively heavy anion, thus decreasing their performance in an NF.sub.3 --F.sub.2 gas generator. This disadvantage can be overcome by replacing the SbF.sub.6.sup.- or AsF.sub.6.sup.- anion by the lighter PF.sub.6.sup.- anion. The existence of this salt has previously been claimed by Tolbert et al in U. S. Pat. No. 3,708,570, but their production process was so inefficient that they could not isolate an amount of material sufficient for its isolation, identification and characterization.